*{
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
img{
  /* 去除掉图片默认的3px */
  display: block;
  // vertical-align: middle;
  width: 100%;
}
a{
  text-decoration: none;
  /* 让a标签的字体颜色 继承 */
  color: inherit;
}
ul{
  list-style: none;
}
input{
  border: none;
  outline: none;
}
.clearfix::after{
  content: "";
  display: block;
  height: 0;
  line-height: 0;
  visibility: hidden;
  clear: both;
}